Folding machine with two pivotally mounted plates



Sept. 29, 1964 H. c. LOCKWOOD ETAL 3,150,872

FOLDING MACHINE WITH Two PIVO'VIALLY MOUNTED, PLATES Filed Aug. 13, 1963 5 Sheets-Sheet 1 ATTORNEY Sept. 29, 1964 H. c. LOCKWOOD ETAL 3,150,372

FOLDING MACHINE WITH TWO PIVQTALLY MOUNTED PLATES Filed Aug. 15, 1963 5 Sheets-Sheet 2' T1 gi INVENTORS flap/7:56. lac/(W400 77/0/1445 1M Mam/wavy ATTORNEY Se t. 29, 1964 H. c. LOCKWOOD ETAL I 3,150,372

FOLDING MACHINE WITH TWO PIVOTALLY MOUNTED PLATES Filed Aug. 13, 1963 1 5 sheets sheet 3 16 464656! Z aa wa a 0 77/0/1445 M MeA nvo/w v BY w? ATTORNEY H. c. LOCKWOOD .ETAL 3,150,872

Sept. 29, 1964 FOLDING MACHINE WITH TWO PIVOTALLY MOUNTED PLATES Filed Aug. 13, 1963 5 Sheets-Sheet 4 Y 0 WM m N i 4M Sept. 29, 1964 H. c. LOCKWOOD ETAL 3,150,372

FOLDING MACHINE WITH 'rwo PIVOTALLY MOUNTED PLATES Filed Aug. 13, 1963 5 Sheets-Sheet 5 INVENTORS 49/ Aafin c5 6'. lac/(W000 i ATTORNEY United States Patent 3,150,872 FQLDENG MACHINE WITH TWO PTVOTALLY MOUNTED PLATES Horace C. Lockwood, 142 N. Monroe St., Ridgcwood, N1, and Thomas Wilson McKindary, Totowa Borough, N..ll., assignors, by mesne assignments, to Horace C. Lockwood, Ridgewood, Nil.

Filed Aug. 13, 1963, Ser. No. 301,769 9 Claims. (Cl. 27tl-79) The present invention relates to an apparatus for fold ing a sheet or web of flexible material, and more particularly to an apparatus for creasing and folding shee. or webs of flexible material such as paper at regularly separated intervals to obtain a zigzag or fan-fold.

It is an object of the present invention to provide an apparatus that will continuously fold sheets or webs of flexible material such as paper alternately in opposite directions to form a zigzag or fan-folded pack at big. speed without injuring the web.

It is a further object of the present invention to provide an apparatus that will continuously and accurately properry register the point of folding with respect to the sheet material whether or not said sheet material has been previously perforated or scored along the proposed fold line. In this connection it is an object of the invention to provide means for applying suihcient pressure at the time of the making of the fold or crease so that a sharp flat fold is obtained without the necessity of previously perforating or scoring the sheet material. This last mentioned attribute of the invention permits direct delivery of the zigzag folded pack to a conveyor without the use of a stacker even where folding a very light or very narrow web material.

it is still another object of the present invention to provide an apparatus which will accommodate material of varying thicknesses. One of the disadvantages of the devices presently available is the inability of these devices to handle at high speed material which has a thickness of less than .004 inch. A device embodying the present invention will properly fold and stack sheet material having a thickness of less than .002 inch.

A device embodying the present invention may be simply and easily adjusted to accommodate different widths of web or sheet material without the necessity of substituting any new parts and without the necessity of making any complicated or length adjustments in the machine. In like manner the length of web between the folds to be imparted by the device to the web material may be quickly and readily adjusted.

It is still another object of the present invention to provide an improved folding machine that will operate at high speed in a quiet and smooth manner with little or no vibration transmitted to its surroundings.

It is also an object of the present invention to provide an apparatus that is durable and reliable and may be manufactured at reasonable cost.

These and other objects and advantages of the present invention will be more readily apparent from the following drawing and description of one embodiment thereof in which drawings:

16. l is a stretched-out partially exploded schematic drawing of all the operational elements of a device embodying the present invention;

FIG. 2 is a side elevation thereof;

FIG. 3 is a sectional view taken along line 33 on FIG. 2;

FiG. 4 is a sectional view taken along line 44 on FIG. 2;

PEG. 5 is a sectional view taken along line 55 on FIG. 2;

ice

FIG. 6 is a sectional view taken along line 66 on FlG. 5; and

FIGS. 7, 8, 9, l0 and 11 are diagrammatic views illustrating the various positions of the web and folding plates during the folding cycle.

PEG. 1 shows diagrammatically the essential operational elements of the apparatus and the over-all operation of the device can be best appreciated therefrom; the web W is not shown so that the various parts of the apparatus may be seen more clearly.

As seen in FIG. 2 the web W which is to be alternately folded into a zigzag fold pack of uniform portions is fed into the machine over a centrally located. guide roller 10 from a supply source not shown. From guide roller 10 the web W is led through reciprocating guide rollers 11 and 12 to the folding plates 14 and 15. After folding the folded web material is carried away from the machine by conveyor 16.

All of the moving elements of the machine are driven by motor 17 through cam shaft 18 and the entire apparatus is mounted on and carried by frame 19.

In operation the web material W is held in position during the folding cycle by air suction supplied by air pump 2% driven by motor 21.

The folding plates 14 and 15 are driven from the cam shaft 18 through rods 22 in a reciprocal or oscillating movement, moving from the vertical position as shown for folding plate 14 to the horizontal position as shown for folding plate 15 and then returning to the vertical position. The folding plates 14 and 15 are each carried by a shaft 23 the outer cylindrical ends of which are journalled in bearings 24 mounted on frame 19. The central portion 25 of each shaft 23 is cut from rectangular stock and is U-shaped to receive the folding plates 14 and 15. Channels 26 are provided inside the U-shaped portion 2 5 of shafts 23 to receive gibs 27 secured to the back face of the folding plates 14 and 15. The folding plates 14- and 15 are held in position with respect to the shaft 23 by set screws 28.

The rods 22 which drive the folding plates 14 and 15 are connected to shafts 23 by crank arms 30, the crank arms 3d being tightly mounted to one end of each of the shafts 23 and pivotally secured by pin 31 to rods 22.

At their lower ends the rods 22 are provided with yokes 32 which have the centrally located slots 33 into which the shaft 18 is slidably fitted. Timed reciprocal motion is imparted to the folding plates 14 and 15 through rods 22 by cam 34 securely mounted on cam shaft 13 and follower 35 which is mounted for rotation around pin 36 to yoke 32. Tension springs 38 secured at one end to rods 22 and at the other end to frame 19 urge the rods 22 downwardly so that the cam followers 35 are held firmly against earns 34. The cams 3-4 are shaped to impart substantially reciprocal motion to the rods 22 which through cranks 30 move the folding plates 14 and 15 in an oscillating motion from the vertical position shown for plate 15 to the horizontal position shown for plate 14 and then back up again. The cams 34 are so shaped and positioned on cam shaft 18 that the oscillating movement of the folding plates 14 and 15 is timed with respect to one another to prevent the folding plates 14 and 15 from interfering with one another as they move from the horizontal to the vertical position. To accomplish this the cams provide a short dwell period after the folding plate reaches the vertical position.

The timing relationship between the folding plates 14 and 15 is such that the cam 34 associated with folding plate 14 does not permit the folding plate 14 to start its downward movement until the cam 34 associated with folding plate 15 has moved the folding plate 15 suificiently out of the way to prevent interference between the two folding plates 14 and 15. This can be better appreciated from FIGS. 7 through 11 and will be described in greater detail hereinafter.

As pointed out above, all of the moving parts of the device are driven by motor 1'7 which is connected to cam shaft 18 by drive belt it) to drive the cam shaft 13 at constant speed. Because of the fact that all of the moving parts receive their impetus for movement from the single cam shaft 15 a properly timed relationship between the movement of the parts is easily obtained.

The leading edge 43 of each of the folding plates 14 and 15 is sharp and as the folding plate brings the web W downwardly the leading edge 43 imparts an initial crease along the prospective fold line of the web N. This crease is thereafter firmly impressed into the web W by the opposite folding plate which presses the web W at the point of crease between the'folding plate and one of the anvils 44 and it. The anvils 44 and 45 are securely fastened to the frame 19 by bolts 4.6 (see PEG.

In order to make sure that the folding plate is exactly vertical "in its uppermost position the portion of the plate below the shaft 23 strikes the anvil as which acts as a step. A slotted connection between rods 22 and crank 36 at pin 31 prevents overdrive which could unduly strain the parts.

In order to hold the web W in proper position with respect to the folding plates 14 and 1S and the anvils 44 and 45 during the folding cycle air suction is used. This suction is applied to the web W through a series of ports 47 located adjacent to the leading edge 43 of each of'the folding plates 14 and 15 and a series of ports 43 located along the upper surface of each of the anvils 44 and 45.

By means of the air suction delivery system illustrated the suction is delivered to the ports 4" in folding plate 14 and the ports 43 in anvil 44 simultaneously, at which time no suction is being transmitted to the ports 47 in folding plate 15 and the ports 48 in anvil 45. To accomplish this the ports 4-7 in plate 14 are linked together with the ports 48 in anvil 44 by flexible tube 4? and the ports 47 in plate 15 and the ports 43 in anvil 45 are linked together byrflexible tube 5th. In the position shown in FIGS. 1 and 2 the suction created by pump 2% has just been transferred from folding plate 15 and anvil 45 to folding plate 14- and anvil 44.

The air vacuum pump 2%) creates the suction which is transmitted to valve 51 by flexible hose 52. Valve 51 directs the transmission of suction either through flexible hose 54, vacuum break 55 and flexible hose 56 to folding plate 14 and anvil 44, or through flexible hose 5%, vacuum break 59 and flexible hose 6%) to folding plate 15 and anvil 45.

As can best be seen in FIG. 2 the suction is transmitted through flexible hose 52 to aperture 61 in the base of valve 51. Valve cylinder 62. controls the transmission of the suction to either flexible hose 54 or flexible hose 58. To accomplish this the valve cylinder 62 is mounted for slidable movement within valve casing 63 and provided with appropriate gaskets to prevent air leakage.

In the position shown in FIG. 2 the aperture 61 in the valve casing 63 is lined up with port 65 in cylinder 62. Through this port 65 the suction is transmitted to flexible hose 54 through chamber 66 and port d7 which is in line with opening 63 in valve casing 63.

To shift the suction from flexible hose 54 through which it is transmitted to folding plate 14 and anvil 44 to flexible hose 58 through which the suction will be transmitted to folding plate 15 and anvil 45 the valve cylinder 62 is moved to the left as seen in FIG. 2. After such movement port 70 in cylinder 62 will be aligned with aperture 61 in the valve casing 63 and the suction will be transmitted to flexible hose 58 through chamber 56 and port 71 in the valve cylinder 62 and port '72 in the valve casing 63, which ports will also be aligned after the movement to the left of the cylinder 62.

As can best be appreciated from FIG. 1 the movement of the cylinder 62 is controlled by cam 73 which cam is securely mounted on cam shaft 18. Arm 74 pivotally mounted to the frame 19 by pin 75 carries at its lower end a cam follower 76 and at its upper end it is pivotally mounted to the outer end of cylinder 62,. Spring '77 is provided to hold the cam follower '76 firmly against the face of cam '73 to insure proper movement of the valve cylinder 62.

Both folding plates 14 and 15 are substantially identical in construction as are the anvils 44 and 45. A description of the features of either set of folding plate and anvil is therefore deemed sufficient. As can best be seen in FIGS. 5 and 6 the suction is transmitted by flexible hose 56 to L connection 79 where it is divided and conveyed to ports 4% in the anvil 44 and the ports 47 near the leading edge 43 of folding plate 14. The anvil 44 is provided with a hollow chamber 89 through which the suction is transmitted to the ports 43 in the upper face of the anvil 44. In a similar manner the plate 14 has mounted on its back face a casing 81 which provides a chamber 82 for conducting the suction to the ports 47.

It should be noted that the ports 47 in the front face of folding plate 14 are provided only along a line slightly less in width than the web W being folded by the apparatus. In like manner the ports 48 in anvil 44 are located in a length limited in extent to the width of the web W.

his is necessary to insure a positive suction grip on the web W along substantially its entire width. Any open ports extending beyond the edge of the Web W would create a substantial loss of suction force and reduce the effective gripping power of the air vacuum being used.

In order to insure a positive release of the suction force being applied to the web W at the proper moment in the folding cycle the vacuum breaks 55 and 59 are pro- 7 vided. Each of the vacuum breaks 55 and 5 comprises a cylindrical cup 84 and a tight-fitting top 85'. When the top 85 is moved away from the cup 84 into the position illustrated for vacuum break 59 there is a complete release of suction at the ports 47 in folding plate 15 and the ports 48 in anvil 4-5. Upon closure of the vacuum break with the top 35 held firmly against the cup 84 as illustrated for vacuum break 55 there is a positive seal in the line leading to the folding plate and anvil permitting the complete transmission of the air suction created by air pump 20.

In order to accomplish the desired timed positioning of the tops 85 relative to the cups 84, came 36 are provided to control this movement. Each of the tops 85 is carried at the outer end of an arm 87 which is pivotally mounted to strut 83 at pivot point 89. The motion of the arm 87 and the top 85 carried thereon is controlled by cam follower 9i) mounted on the arm 8'7. The cam follower is held firmly against earns 86 by springs 91 which are secured at one end to the frame 19 and at the other end to the arms 87.

The earns 86 which are securely fastened to cam shaft 18 are so shaped to lift the top 85 away from its associated cup 84 to break the suction in the line then transrnitting the suction to the ports 47 and 48 just slightly before the movement of valve cylinder 62 which will transfer the suction to the other line.

In order to insure proper positioning of the web W as it is being fed to the folding plates 14- and 15 the guide rollers 11 and 12 are carried in carriage 4 which is moved in a reciprocating motion by arm 95. The drive for arm 95 is taken from cam shaft 18 by belt 96 which drives idler shaft 9'7 mounted to frame 19 by bearlugs 98 and thence from idler shaft '97 to crank shaft 9 through belt 1%.

The crank shaft 9 is mounted to the frame 19 for rotation in bearings 101. Securely fastened at one end to the crank shaft f9 for rotation therewith is crank 103. Link N4 is pivotally connected at one end to crank 1&3 by pin Hi5 and at the other end is pivotally connected to the arm 95. On rotation of the shaft 99 the crank I43 drives the arm 95 through link 104 in an oscillating movement as indicated in FIG. 2. Rod res pivotally mounted at one end to arm 95 and at the other end to carriage 4 moves the carriage 94 in a reciprocal movement within channels 147 formed in the upper horizontal portion of frame 19.

The movement of the carriage 94 is synchronized with the movement of the folding plates 14 and 15 by cam shaft in; so that the feed point of the web W is positioned directly above the leading edge 43 of the folding plate 14 or 15 which is in the vertical position just at the time that such folding plate starts its downward motion and thereafter as the folding plate moves downwardly the web W lags slightly behind the leading edge 43 until the folding plate reaches its horizontal position.

The conveyor 16 which carries the finished folded web away from the apparatus is driven from idler shaft 97 by belt 1%.

In the folding operation the initial crease is placed in the web by the leading edge 43 of the folding plates 14 and 15 as the plate moves from the vertical position shown for folding plate E4 to the horizontal position shown for folding plate 15. A positive and sharp fold is thereafter obtained by pressing the web W between the opposite folding plate and anvil. In order to accommodate webs of different thicknesses and to assure positive pressure being applied to the web at this point in the folding cycle the bearings 24 which carry shafts 23 are resiliently mounted to the frame if. This can best be seen in FIG. 5. To provide this resilient mounting a compression spring All) is located between the head of bolt 111 which passes through the horizontal flange of bearing 24 to permit vertical movement of the bearing 24 relative to the frame 19 and the anvils 44 and 45 securely mounted to the frame 19. The bolt HT. is threaded into heavy washer 112 and securely held against movement relative to the frame 19 by nut 113.

in order to accommodate webs of varying widths up to the limit of the width of the folding plates 14 and 115 it is necessary only to cover up the ports 47 in the folding plates 14 and I5 and the ports 48 in anvils 44 and 45 outboard of the outer edges of the web W being operated on by the machine. Thin pressure-sensitive tape has been found to be a suitable device to perform this function.

The operation of the machine can best be appreciated from FIG. 1 and FIGS. 7 through 11. Starting at the point in the cycle with folding plate 14 in its uppermost or perpendicular position and folding plate 15 in its lowest or horizontal position the suction created by air pump 2% has just been transferred by valve 51 to the ports 47 along the upper edge of the folding plate 14 and ports 48 in the upper surface of anvil 44. Suction firmly grips the web W and holds the web W in a fiat taut relationship against the surface of the folding plate 14 with the crease that has just been formed by the leading edge 43 of plate 15 resting along the pivot point of folding plate 14 in the position shown in FIG. 7.

The suction will continue to be applied through the ports 47 in folding plate 14 and the ports 48 in the anvil 44 until the folding plate 14 has moved completely through one-half cycle to its horizontal position.

With the web W thus held in position by suction, the folding plate 15 begins to swing away from anvil 44 in a clockwise direction around the center point of its shaft 23 so that it will be located in a position which will not interfere with clockwise pivoting of plate 14. Until the plate 15 has moved into such a position where it will be clear of plate 14 the cam 34 associated with the rod22 which drives the folding plate 14 will not start plate 14 into its downward or clockwise pivotal movement.

In order to accommodate this dwell time in the cycle the crank 1% through arm 95 and rod 106 continues to move the carriage 94 carrying guide rollers 11 and 12 to the left as seen in FIGS. 7 and 8. This increases the smooth operation of the machine.

Since at this point in the cycle no suction is being applied at the ports 47 in the folding plate 15 the plate is free to move away from the web W without adherence of the Web W thereto. In like manner, since no suction is being applied at ports 48 in anvil 45, as the front surface of the plate 15' is moved away from the horizontal portion of the web W located between the anvils 44 and 45, and away from the upper surface of anvil 45, the portion of the web W held between the plate 15 and the anvil 45 is released and will fall through the action of gravity toward the conveyor 16. The suction in ports 48 of anvil 44 will prevent the web W from slipping out of the closing angle formed by the face of folding plate 14 and the upper surface of anvil 44 until the web W is tightly clamped between those two surfaces.

When the folding plate 15 has moved to a position Where it will no longer interfere with clockwise movement of folding plate 14 the cam 34 through rod 22 associated with folding plate 14 will start folding plate 14 to move in a clockwise direction toward a horizontal position. At this same time crank 103 begins moving the carriage 94 to the right as seen in FIGS. 7 through 11 so that the web W will be held in a position slightly behind the leading edge 43 of the plate 14 as the plate moves downwardly in a clockwise direction toward the horizontal position. This part of the cycle can be seen in FIGS. 9 and 10. During the clockwise movement of the folding plate 14 the next section of the Web W is taken from the Web supply source. Any convenient supply tension means can be provided to keep the web W taut until it is picked up by the suction in ports 47 in plate 15 and the ports 48 in anvil 45.

As the folding plate 14 moves in a clockwise direction it grips the crease in the web W located between plate 14 and anvil 44 and exerts pressure along the fold line to impart a sharp positive crease in the web W. The resilient mounting of the shafts 23, as can be best seen in FIG. 5, permits the application of positive pressure along the fold line of that part of the web W held between folding plate 14 and anvil 44.

When the plate 14 reaches the horizontal position with its upper end and leading edge 43 resting on anvil 45, as shown in FIG. 11, the cam 36 associated with vacuum break 55" will act to lift top away from cup 84 thereby breaking the suction being applied through ports 47 in folding plate 14 and ports 48 in anvil 44. At this instant in the cycle no suction is being applied to the web W by either sets of ports 47 or 43.

Some time during the clockwise movement of the plate 14 about midway between its vertical and horizontal position the cam 36 associated with vacuum break 59 will release the top 85, permitting spring 91 associated therewith to firmly seat the top 35 onto cup 84 of the vacuum break 59.

Immediately after vacuum break 55 has been moved to the open position the cam '73 acting through arm 74 will shift valve cylinder as to the left, as seen in FIG. 2, so that the suction created by pump 29 will be shifted from flexible hose 54 to flexible hose 58 and thereby conveyed to the ports 47 in plate 15 and the ports 48 in anvil 45. At this point in the cycle the carriage 94 has brought the web W into a position where it is perpendicular and stretched taut over the face of folding plate 15. The suction in ports 47 in plate 15 and ports 4% in anvil 45 grasps the web W and holds it firmly in position against the face of folding plate 15.

Folding plate 14 then starts to move in a counterclockwise direction away from anvil 45 pivoting around the center of its shaft 23. While this movement occurs carriage 94 continues to move to the right, as seen in FIG. 11, to give time for folding plate 14 to swing into a position where it will no longer interfere with a counterclockwise downward movement of folding plate 15. The second half of the folding cycle is then carried out exactly the same as that for the first half of the cycle ex- 2,1 sas /:2

5 cept that it is now plate that carries the portion of the web W and folding plate 14 that is first moved out of the way. When folding plate 14 has reached the vertical position and folding plate 15 has'returned to the horizontal position shown in PEG. 7 the cycle is complete and ready to be repeated.

It is important to note that the length of the web W between the folds formed in the web depends upon the distance between the leading edge 43 of the folding plates 14 and 15 and the pivot point for these folding plates. It is essential that the center of the shaft 23 carrying each of the folding plates 14 and 15 be positioned along the line of fold. Therefore, when plate 15 is in the horizontal position its leading edge 43 lies along the axis of rotation of the shaft 23 carrying folding plate 14, and in like manner, when the plate 14 is in a horizontal position its leading edge 4?? lies along the axis of rotation of the shaft 23 carrying folding plate 15. The axis of pivoting for folding plate 1 5 and the axis of pivoting for folding plate 15 are parallel to one another and the distance between the two is equal to the length of web W desired between folds.

By increasing or decreasing the distance between the center lines of the shafts 23 the size of the portion of the web W between the fold lines imparted to the web W by the apparatus may be adjusted. To accomplish this nuts 113 are loosened and the bearing assemblies 24 carrying the shafts 23 are then moved an amount equal to V2 the change in size desired with the bolt ill sliding in slot 114.

This movement of the bearings 24 will change the dis tance between cam followers 35 and the pins 31 which connect cranks 3 5* and rods 2.2,, in order to accommodate this change in distance, threaded members 115 are inserted in rods 22 so that the effective length of the rods 22 can be adjusted.

The operable length of the folding plates 14 and 15 is then simply adjusted by loosening set screws 28 and moving the plates 14 and 15 by sliding the gibs 27 in channels 26 formed in the central portion of shafts 23. When the leading edge 43 of each of the folding plates 14 and 15 is again lined up with the axis of the shafts 23, set screws 28 are tightened and the folding plates 14 and 15 will be properly held in their new position.

The anvils 44 and 45 are then moved into proper position underneath the folding plates 14 and 15. To permit this movement slots are provided in the outer ends of anvils 44 and 4-5 through which the bolts 46 pass. By loosening the bolts to the anvils 44 and 4-5 can then be moved to their new position and refastened by tightening up bolts 46.

A change in the distance between the two shafts 23 carrying folding plate 14 and 15 also necessitates a change in the effective distance of travel of carriage Wt.

To adjust this the pin 165 between the link 1% and the crank 193 is moved within the slot located in crank res, thereby changing the length of stroke that will be imparted to carriage 94.

What We claim is:

l. A flexible material folding machine comprising two folding plates each pivotally mounted for separate reciprocal movement about an axis, the axes of rotation of said folding plates being parallel to one another, means for reciprocally pivoting said folding plates about said axes in a timed relation to one another, means for feeding said'ilexible material into a position where it overlies one of said folding plates, means for releasably gripping a portion of said flexible material to hold it in a fixed position relative to one or the other of said folding plates; an anvil adjacent to each of said folding plates and presenting a surface underlying the folding plate as to which it is adjacent when said folding plate has been pivotably moved into its lowermost position; the surface presented by each of said anvils lying in the same plane as the axes of rotation of the folding plate to which it is adjacent and means for resiliently mounting said axes of rotation for the folding plates to permit movement of said axes of rotation of said folding plates out of the plane containing the surfaces presented by said anvils.

2. A flexible material folding maclune comprising two folding plates each pivotally mounted for separate reciprocal movement about an axis, the axes of rotation of said folding plates being parallel to one another, means for reciprocally pivoting said folding plates about said axes in a timed relation to one another, means for feeding said flexible material into a position where it overlies one of said folding plates, means for releasably gripping a portion of said flexible material to hold it in a fixed position relative to one or the other of said folding plates; an anvil adjacent to each of said folding plates and presenting a surface underlying the folding plate as to which it is adjacent when said folding plate has been pivotally moved into its lowermost position; each of said anvils being provided with means for releasably gripping said flexible material; means to simultaneously activale the gripping means associated with one of the folding plates and the gripping means associated with the anvil adjacent to and underlying said folding plate, means for simultaneously releasing both said gripping means when said folding plate reaches a predeterr ined position in its reciprocal movement about its axis, and means for simultaneously activating the gripping means associated with the other of said folding plates and the gripping means associated with the anvil adjacent to and underlying said other folding plate, and means for releasing both said gripping means associated. with the other folding plate and anvil when said other folding plate reaches a predetermined position in its reciprocal movement about its axis.

3. A flexible mate 'ial folding machine as claimed in claim 2 including timing means for actuating and releasing all of said gripping means and wherein each of said folding plates is adapted for reciprocal movement be tween an uppermost substantially vertical position and a lowermost substantially horizontal position, and wherein said timing means aotuates the gripping means as sociated with one of said folding plates and with the anvil adjacent to and underlying said folding plate while said folding plate moves from its uppermost position to its lowermost position and said gripping means is released after said folding plate reaches its lowermost position.

4. A flexible material folding machine comprising two folding plates each pivotally mounted for separate reciprocal movement about an axis, the axes of rotation of said folding plates being parallel to one another, means for reciprocally pivoting said folding plates about said axes in a timed relation to one other, means for feeding said flexible material into a position where it overlies one of said folding plates, each of said folding plates having a leading edge furthest from its axis of rotation lying along a straight line parallel with said axis of rotation, a first means for releasably gripping a portion of said flexible material to hold it in a fixed position relative to one or the other of said folding plates, said first means being located adjacent to the leading edge of each of said folding plates, and a second means for releasably gripping a portion of said flexible material, said second means being located adjacent to the axes of each of said folding plates, means to simultaneously activate the gripping means adjacent to the leading edge and the gripping means adjacent to the axis of rotation of one of said folding plates, means for simultaneously releasing both said last mentioned gripping means when said folding plate reaches a predetermined position in its reciprocal movement about its axis means for simultaneously activating both gripping means associated with the other of said folding plates and means for releasing both said last mentioned gripping means associated with the other of said folding plates when said other folding plate reaches a predetermined position in its reciprocal movement about its axis; an

YA! anvil adjacent to each of said folding plates and presenting a surface underlying the folding plate as to which it is adjacent when said folding plate has been pivotably moved into its lowermost position.

5. A flexible material folding machine as claimed in claim 4, including timing means for actuating and releasing all of said gripping means and wherein each of said folding plates is adapted for reciprocal movement between an uppermost substantially vertical position and a lowermost substantially horizontal position and wherein said timing means actuates the gripping adjacent to the leading edge and the gripping means adjacent to the axis of rotation of one of said folding plates while said folding plate moves from its uppermost position to its lowermost position and releases said gripping means after said folding plate reaches its lowermost position.

6. A flexible material folding machine comprising two folding plates each pivotally mounted for separate reciprocal movement about an axis, the axes of rotation of said folding plates being parallel to one another, means for reciprocally pivoting said folding plates about said axes in a timed relation to one another, means for feeding said flexible material into a position where it overlies one of said folding plates, means for releasably gripping a portion of said flexible material to hold it in a fixed position relative to one or the other of said folding plates; an anvil adjacent to each of said folding plates and presenting a surface underlying the folding plate as to which it is adjacent when said folding plate has been pivotably moved into its lowermost position; each of said folding plates having a leading edge furthest from its axis of ro tation lying along a straight line parallel with said axis of rotation, said leading edge of each of said folding plates being so located that it lies along the axis of rotation of the other of said folding plates when said leading edge of the folding plate is in its lowermost position.

7. A flexible material folding machine comprising two folding plates each pivotally mounted for separate reciprocal movement about an axis, the axes of rotation of said folding plates being parallel to one another, means for reciprocally pivoting said folding plates about said axes in a timed relation to one another, means for feeding said flexible material into a position where it overlies one of said folding plates, means for releasably gripping a po"- seem tion of said flexible material to hold it in a fixed position relative to one or the other of said folding plates, each of said folding plates having a leading edge furthest from its axis of rotation lying along a straight line parallel with said axis of rotation, said leading edge of each of said folding plates being so located that it lies along the axis of rotation of the other of said folding plates when said leading edge of the folding plate is in its lowermost position.

8. A flexible material folding machine as claimed in claim 7, including a member cooperating with each of said folding plates to impart a positive crease in said flexible material.

9. A flexible web folding machine comprising two folding plates each pivotally mounted for separate reciprocal movement'about an axis, the axes of rotation of said folding plates being parallel to one another, means for reciprocally pivoting said folding plates about said axes in a timed relation to one another, means for feeding said flexible Web into a position Where a portion of it overlies one of said folding plates, means for releasably gripping said portion of said flexible web to hold it in a fixed position relative to one or the other of said folding plates; an anvil adjacent to each of said folding plates and resenting a surface underlying the folding plate as to which it is adjacent when said folding plate has been pivotally moved into its lowermost position; means to simultaneously activate the gripping means associated with one of the folding plates, means for simultaneously releasing said gripping means when said folding plate reaches a predetermined position in its reciprocal movement about its axis, and means for simultaneously activating the gripping means associated with the other of said folding plates, and means for releasing both said gripping means associated with the other folding plate when said other folding plate reaches a predetermined position in its reciprocal movement about its axis.

References Cited in the file of this patent UNITED STATES PATENTS 7,079 Carey et al Feb. 12, 1850 568,307 Meisel Sept. 22, 1896 2,399,926 Leibold Aug. 18, 1959 3,083,008 Miller Mar. 26, 1963 

1. A FLEXIBLE MATERIAL FOLDING MACHINE COMPRISING TWO FOLDING PLATES EACH PIVOTALLY MOUNTED FOR SEPARATE RECIPROCAL MOVEMENT ABOUT AN AXIS, THE AXES OF ROTATION OF SAID FOLDING PLATES BEING PARALLEL TO ONE ANOTHER, MEANS FOR RECIPROCALLY PIVOTING SAID FOLDING PLATES ABOUT SAID AXES IN A TIMED RELATION TO ONE ANOTHER, MEANS FOR FEEDING SAID FLEXIBLE MATERIAL INTO A POSITION WHERE IT OVERLIES ONE OF SAID FOLDING PLATES, MEANS FOR RELEASABLY GRIPPING A PORTION OF SAID FLEXIBLE MATERIAL TO HOLD IT IN A FIXED POSITION RELATIVE TO ONE OR THE OTHER OF SAID FOLDING PLATES; AN ANVIL ADJACENT TO EACH OF SAID FOLDING PLATES AND PRESENTING A SURFACE UNDERLYING THE FOLDING PLATE AS TO WHICH IT IS ADJACENT WHEN SAID FOLDING PLATE HAS BEEN PIVOTABLY MOVED INTO ITS LOWERMOST POSITION; THE SURFACE PRESENTED BY EACH OF SAID ANVILS LYING IN THE SAME PLANE AS THE AXES OF ROTATION OF THE FOLDING PLATE TO WHICH IT IS ADJACENT AND MEANS FOR RESILIENTLY MOUNTING SAID AXES OF SAID AXES OF ROTATION OF SAID FOLDING PLATES OUT OF THE PLANE CONTAINING THE SURFACES PRESENTED BY SAID ANVILS. 